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mattm1962
07-21-2006, 09:52 AM
Are granite screenings and stone dust the same thing? I live in SC so the winters are fairly mild and I am looking for a suitable material for a paver base and setting bed. Can granite screenings be used?

McKeeLand
07-21-2006, 11:49 PM
You should never use screenings as a paver base, however so many guys do it. If you insist on using them, at the very least set your pavers in concrete sand or equivalent. the problem with screening is that when u use them as a setting bed they do not push up between the joints of the paver when tamped, thus creating the very important interlock. The pavers are then vournable to horizontal shift and wash out. i've seen many times. You should consider using a crushed stone base or at least a recycled concrete too, instead of stone dust. Pavers are alot of work and money, so why cheap out on a couple dollars a ton in materials and a few extra man hour labor to do it right. Done right they will out last you.

mattm1962
07-24-2006, 01:07 PM
Thanks for the info. Another question... is concrete sand and masonry sand the same thing? If not, can masonry sand be used as a setting bed and/or finishing sand for sweeping between the joints?

McKeeLand
07-24-2006, 06:45 PM
Concrete sand has a lot more large stones than mason sand. You need to use concrete sand for the bedding. You can use mason sand in the joints if you like. It goes in a little easier than concrete, but when you tamp the concrete sand in the joints it tends to crush down all of the little stones much smaller. We just use the concrete sand rather than truck in two different sand to the job, especially if it is a tumbled paver.

mattm1962
07-25-2006, 01:49 PM
Once again thanks for your feedback. I have a couple more questions about base material. I have read where crusher run makes a good paver base. What are your thoughts on that? It seems to be a little chunky to me so I was wondering if it will compact well. I can get 10 tons delivered for $175 which seems like a reasonable price, although I don't think I need anywhere near that much... I have about 420 sq. ft. worth of patio and walkway that I am doing. Also, if I use CR, how deep should I make the base? This patio and walkway is for foot traffic only. I want to do it right, but if it makes any difference as to the depth of the base, I don't have to worry about freezing/thawing related problems since I live in SC. I have been trying to find concrete sand for the setting bed and joints but I am not having much luck.

McKeeLand
07-25-2006, 11:13 PM
I am not familiar with crusher run, they have many names for this stone, quarry blend, road stone, 2a modified. As long as it has a good mix of 1" stone to fine screening like particles and every size in between should be fine. you need the different sizes to fill in all of the air spaces between the large stone when compacted and you need the large stone to give the base strength. 10 tons actually may be a little short. Figure 1000lbs of material will cover 100sf at 1" depth. Also figure 30% for compaction. 4" is the absolute min depth and 6" is the recommended up here. That's more to do with settlement than frost though. The deeper the base the stronger it is. Also make sure you have a min 8" over dig, i go with 12" to be safe. That means that you base should extend 8" beyond the edge of the pavers. Also, check with your local concrete plant for the sand. If they dont sell it they can tell you where to get it. i would think in SC you would have all the sand you could want. Hope this helps.

mattm1962
07-27-2006, 09:44 PM
I ordered the crusher run which sounds like the same thing you referred to in your post. I am getting max 3/4" stone down to fines. I also finally found a place where I can get concrete sand. For whatever reason, most of the places I called either didn't have concrete sand or told me it was the same as masonry sand. Anyway, I have a couple more questions. I have read where some people install landscape fabric. Is that necessary? If its not worth the trouble and expense I would prefer to skip it. If its a good idea, does it go underneath the base or on top of the base? Also, do you have anymore tips, advice, things I should watch out for, etc? I am a pretty good do-it-yourselfer but this is my first stab at working with pavers and I want to do it right the first time and not screw up and have to do anything over, so anything else you could offer would be appreciated. Thanks!

McKeeLand
07-27-2006, 11:07 PM
The fabric that you should use is actually a Geo textile. Its not just a weed fabric like you get at Home depot, but is an actual structural fabric. Mirafi is the company I'm familiar with that makes itt is a good step to do for a few reasons. However the one problem is that i have never seen it in any thing smaller than a 12' x 400' roll at around $475. It doesn't make sense to buy it for one job. For years we installed pavers with out it, it is just an extra precaution. There are many tips i could give you, but the most important ones are about compaction. Always compact you sub base, or the ground after you excavate for the pavers. Compact your base in max 4" lifts of stone. Compact your pavers once after laying them before you sweep the joint sand, and then once after you sweep the sand in. Those are some of the key things. If you have more specific questions, feel free to ask. Hope this helps.

mattm1962
07-28-2006, 02:42 PM
I know compaction is a very important part of a quality paver job. However, I am figuring that installing my patio and walkway will take me at least 4 days...and that's probably if all goes well. Renting a plate compactor will run me about $60 per day. This project is starting to get a little pricey so do you think that compacting the base with a hand tamper will be sufficient? Also, I am trying to figure out the best way to approach this project since I don't have several days in a row to devote to it... I only have weekends and evenings. Can I excavate the patio and walkway, add and compact the base material and leave it for a few days before adding the setting bed and laying the pavers? Or do I need to get the pavers down as soon as possible in the event of rain? I don't know what affect rain might have on the exposed base and/or setting bed. Thanks for your feedback!

McKeeLand
07-28-2006, 06:36 PM
The rental of the plate tamper is the always the biggest dilemma with pavers. i remember when i was first getting started and we didn't do enough pavers to own a plate. We would waste so much money renting plates, we could have bought 1 or 2 in rental fees before i finally bought one. The best thing is to borrow your buddies.:laugh: However if you are careful when you excavate the subase and don't over excavate with you sandy soil you should be fine with hand tamping. You'll get one heck of a tricepe work out.
Your base will be fine letting it sit until your ready to lay pavers. Just try to divert the rain water away from it to keep it from flooding out. It is actually good to have moisture in the stone when compacting. It helps the compaction, you just don't want standing water or water pumping out when you tamp. However don't screed more sand out than pavers you plan on laying that day. If it rains it will mess up the sand that doesn't have pavers on it. You should keep your sand pile covered up with a tarp. Pavers aren't cheap, even when you do them your self, but they take a lot of labor so you can save doing them your self. Of course i tell people that you'll do it your self once, but never again.:cry: